I have normalized data from 4 different water samples (2treatments+2 control) which I have assessed by ANOVA to determine significant differences between the multiple groups; however, I would like to know the respective difference of each group compared to the control. When I look at the posthoc Tukey test there is no significance revealed to a particular group. How to report thee data in the Research paper and how I show
Hi Prachi Arora ,
If things went correctly, ANOVA already should have told you there were no significant results before you did the Tukey, right? From the results from your ANOVA you can thus already cite your output ;). Your citation should look like the following: There is no significant difference in this variable between the groups (Anova, F2,33=13.503, P
Thanks Dirks, but I want to check the significant difference between the multiple water storage containers in which I take 2 as a control and 2 as a treatment for that I use ANOVA with Tukey. I am going in a correct way I think
Prachi Arora, if I understand your question correctly, you can generate a new categorical variable (using treat and cont variables) including four values each representing one of your groups (g1-g4). Next, you create four dummy variables out of this new categorical variable. You can then regress your dependent variable on three of these dummy variables (g2-g4) while treating one of them (g1) as the reference category, to avoid multicollinearity. The coefficients on g2-g4 will tell you the mean difference between each of them and g1. By changing the reference category, you will obtain additional differences you might be interested in. You can further consider applying adjustment (e.g. Tukey) to the p-values for these pairwise comparisons.
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